http://www.helixexams.com Medical Directory en-us Studies in experimental models suggest that endothelium-derived nitric oxide is reduced with aging, and this circumstance may be relevant to atherogenesis. The aim of this study was to determine whether increasing age resulted in altered endothelium-dependent vasodilation in the forearm resistance vessels of healthy humans. Forearm blood flow was measured in 119 healthy subjects, aged 19 to 69 years, by venous occlusion plethysmography. http://hyper.ahajournals.org/cgi/content/full/27/4/849 Sun, 09 Dec 2007 07:54:32 MST http://www.helixexams.com/article/Aging-Progressively-Impairs-Endothelium-Dependent-Vasodilation-in-Forearm-Resistance-Vessels-of-Humans-35.html To test the predictive values of and independent contributions to cardiovascular and all-cause mortality of various arterial parameters exploring characteristics of the arterial wall at different sites, we studied prospectively 110 stable end-stage renal disease patients on hemodialysis. These parameters involved carotid diameter, carotid intima-media thickness, carotid compliance, carotid distensibility, carotid incremental elastic modulus, aortic diameter, aortic pulse wave velocity, and the presence of arterial calcifications measured at the sites of the carotid artery, abdominal aorta, iliofemoral axis, and legs. The results of this study showed that the presence and extent of vascular calcifications were strong predictors of cardiovascular and all-cause mortality. Carotid incremental elastic modulus gave additional predictive value. http://hyper.ahajournals.org/cgi/content/full/38/4/938 Sun, 09 Dec 2007 07:52:55 MST http://www.helixexams.com/article/Arterial-Calcifications-Arterial-Stiffness-and-Cardiovascular-Risk-in-End-Stage-Renal-Disease-34.html In the present study we tested the hypothesis whether an angiotensin AT2 receptor-mediated stimulation of the bradykinin (BK)/nitric oxide (NO) system can account for the effects of AT1 receptor antagonism on aortic cGMP described previously in SHRSP. The effects of ANG II and of losartan plus ANG II on aortic cGMP content were both blocked by cotreatment with the AT2 receptor antagonist PD 123319. http://hyper.ahajournals.org/cgi/content/full/31/1/349 Sun, 09 Dec 2007 07:52:11 MST http://www.helixexams.com/article/AT2-Receptor-Stimulation-Increases-Aortic-Cyclic-GMP-in-SHRSP-by-a-Kinin-Dependent-Mechanism-33.html Chronic treatment of saline-drinking stroke-prone spontaneously hypertensive rats (SHRSP) with agents that interfere with the formation or actions of angiotensin II (Ang II) prevents the development of stroke and renal vascular damage. In both studies, histopathologic examination revealed a marked protective effect of spironolactone against the development of malignant nephrosclerotic and cerebrovascular lesions. These observations indicate a vascular and end organ protective effect of spironolactone in the absence of lowered blood pressure in saline-drinking SHRSP and are consistent with a major role for mineralocorticoids as hormonal mediators of vascular injury. http://hyper.ahajournals.org/cgi/content/full/31/1/451 Sun, 09 Dec 2007 07:50:09 MST http://www.helixexams.com/article/Mineralocorticoid-Blockade-Reduces-Vascular-Injury-in-Stroke-Prone-Hypertensive-Rats-32.html Pulse wave velocity is widely used as an index of arterial distensibility. The aim of this study was to evaluate the accuracy of a new automatic device to measure it and then to analyze the major determinants of pulse wave velocity by application of this device in a large population. We evaluated the accuracy of on-line and computerized measurement of pulse wave velocity using an algorithm based on the time-shifted and repeated linear correlation calculation between the initial rise in pressure waveforms compared with the reference method (manual calculation) in 56 subjects. http://hyper.ahajournals.org/cgi/content/full/26/3/485 Sun, 09 Dec 2007 07:46:12 MST http://www.helixexams.com/article/Assessment-of-Arterial-Distensibility-by-Automatic-Pulse-Wave-Velocity-Measurement-31.html